Effect of STAT3 phosphorylation and p53 expression on human epidermal non melanoma cutaneous tumors

Abstract

To investigate the effect of stat3 phosphorylation and p53 expression on human epidermal non-melanoma cutaneous tumours. Immunohistochemistry technique was employed to measure the expression of p-stat3 and p53 protein in skin tissue from 30 cases of skin squamous cell carcinoma (SCC), 20 cases of basal cell carcinoma (BCC), 20 cases of seborrhoeic keratosis (SK) and 20 normal subjects. (1) p-stat3 protein was abnormally increased in SCC and BCC as compared with normal skin and SK. Expression of p-stat3 in SCC was also significantly higher than that in BCC. (2) Expression of p-stat3 was higher in poorly-differentiated cancers than that in well-differentiated cancers in SCC. The positive rate of p-stat3 expression was correlated with the depth of tumor invasion, but not with tumor size. (3) There was no p53 protein expression on normal skin and SK, it was significantly upregulated in SCC and BCC. In SCC, the intensity of p53 expression was associated with tumor differentiation. There was no correlation between the positive rate of p53 expression and the depth of tumor invasion, whereas the positive rate of p53 expression was correlated with the sun-exposure area. (4) There existed positive correlation between the expression intensity of p-stat3 and p53 in SCC (r=0.641, P<0.05). (1) The overexpression of p-stat3 may play an important role in the development of epidermal tumors. (2) The abnormal activation of stat3 may be related to metastatic potentials in SCC. (3) Both p53 gene and stat3 may contribute to the pathogenesis of skin SCC.